Provided the name doesn't contain commas, then it won't matter if the address does, provided you use 3rd parameter to split. This is a number that specifies how many fields to split the input into. By setting this to 2, everything before the first comma will be treated as the first field--the name. And everything after that first comma, including more commas, will become the second field:

#! perl -slw
use strict;
use Data::Dumper;
##.............................V third parameter
my %hash = map{ split ',', $_, 2 } <DATA>;

print Dumper \%hash;

__DATA__
a name, an address, with commas,
another name, and another address, also with commas
and a third name, and address
fourth name, fourth address
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Produces:

C:\test>junk4
$VAR1 = {
          'and a third name' => ' and address
',
          'a name' => ' an address, with commas,
',
          'fourth name' => ' fourth address
',
          'another name' => ' and another address, also with commas
'
        };
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Note that the addresses are unchomped.